From: Theodore Ts'o tytso@mit.edu
commit 6c1e851c4edc13a43adb3ea4044e3fc8f43ccf7d upstream.
We can do a sleeping allocation from an irq context when CONFIG_NUMA is enabled. Fix this by initializing the NUMA crng instances in a workqueue.
Reported-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Reported-by: syzbot+9de458f6a5e713ee8c1a@syzkaller.appspotmail.com Fixes: 8ef35c866f8862df ("random: set up the NUMA crng instances...") Cc: stable@vger.kernel.org Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/char/random.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -800,7 +800,7 @@ static void crng_initialize(struct crng_ }
#ifdef CONFIG_NUMA -static void numa_crng_init(void) +static void do_numa_crng_init(struct work_struct *work) { int i; struct crng_state *crng; @@ -821,6 +821,13 @@ static void numa_crng_init(void) kfree(pool); } } + +static DECLARE_WORK(numa_crng_init_work, do_numa_crng_init); + +static void numa_crng_init(void) +{ + schedule_work(&numa_crng_init_work); +} #else static void numa_crng_init(void) {} #endif